MIPS: loongson32: ls1c: Fix hang during startup

stable inclusion
from stable-v5.10.143
commit 586f8c8330b72b316cb9a83695ef1f1e62ac6fec
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0U6

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=586f8c8330b72b316cb9a83695ef1f1e62ac6fec



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[ Upstream commit 35508d24 ]

The RTCCTRL reg of LS1C is obselete.
Writing this reg will cause system hang.

Fixes: 60219c56 ("MIPS: Add RTC support for Loongson1C board")
Signed-off-by: Yang Ling <gnaygnil@gmail.com>
Tested-by: Keguang Zhang <keguang.zhang@gmail.com>
Acked-by: Keguang Zhang <keguang.zhang@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: Zheng Zengkai <zhengzengkai@huawei.com>